Pacquiao has improved his skillset as he's moved up in the weights and is no longer struggling to make low weights. That amounts to more energy to maintain the high pace that he does. It spells destruction for his foes.
MAB, JMM and MORALES are all ELITE, great fighters in their own right.... and i mean GREAT, not just really good like hatton..... and although i believe cotto do be really awsome himself hes not in morales/mabs league that and pac has gotten better since then all spell doom to pac opponents.